How Pluto lost its planethood

MIKE BROWN, an astronomer at the California Institute of Technology in Pasadena, didn't set out to kill a planet but to find a new one. The first few objects he spotted on the fringes of the solar system were not quite big enough, but then he saw Xena (now Eris), which may be a shade bigger than Pluto. What followed was a still-controversial series of events that foiled his careful plan to pin down the details before breaking the news. Instead, he hastily called a press conference to announce a new planet.

Brown tells a great tale, interweaving his obsessive planetary quest with falling in love with his wife and the birth of their daughter just before the press conference. He was with them on holiday when the International Astronomical Union voted to demote Pluto from planethood, a story he tells with an amused detachment. Insightful, fun and highly recommended, whatever you think of Pluto.